In current communication electronic technology, a universal serial bus (USB) is commonly used to form a serial communication channel. For example, most computers and laptops use USB interfaces to connect to peripheral devices (e.g., mouse, keyboard, joystick, scanner, external drivers, etc.). Computers can use USB technologies to perform data exchange with portable devices, such as music players, mobile phones, or tablet PCs, while also charging these devices. In such arrangements, the computer may be viewed as a USB host, and the connected peripherals can be viewed as USB devices.